Merge pull request #3224 from Budibase/labday/mike-sql

SQL table manipulation and some external table UI rework

packages/builder/src/components/backend/DataTable/DataTable.svelte

@@ -4,6 +4,7 @@
   import CreateRowButton from "./buttons/CreateRowButton.svelte"
   import CreateColumnButton from "./buttons/CreateColumnButton.svelte"
   import CreateViewButton from "./buttons/CreateViewButton.svelte"
+  import ExistingRelationshipButton from "./buttons/ExistingRelationshipButton.svelte"
   import ExportButton from "./buttons/ExportButton.svelte"
   import EditRolesButton from "./buttons/EditRolesButton.svelte"
   import ManageAccessButton from "./buttons/ManageAccessButton.svelte"
@@ -98,9 +99,7 @@
     on:updatecolumns={onUpdateColumns}
     on:updaterows={onUpdateRows}
   >
-    {#if isInternal}
     <CreateColumnButton on:updatecolumns={onUpdateColumns} />
-    {/if}
     {#if schema && Object.keys(schema).length > 0}
       {#if !isUsersTable}
         <CreateRowButton
@@ -116,6 +115,12 @@
       {#if isUsersTable}
         <EditRolesButton />
       {/if}
+      {#if !isInternal}
+        <ExistingRelationshipButton
+          table={$tables.selected}
+          on:updatecolumns={onUpdateColumns}
+        />
+      {/if}
       <HideAutocolumnButton bind:hideAutocolumns />
       <!-- always have the export last -->
       <ExportButton view={$tables.selected?._id} />

packages/builder/src/components/backend/DataTable/RowFieldControl.svelte

@@ -16,8 +16,8 @@
   export let value = defaultValue || (meta.type === "boolean" ? false : "")
   export let readonly
 
-  $: type = meta.type
-  $: label = capitalise(meta.name)
+  $: type = meta?.type
+  $: label = meta.name ? capitalise(meta.name) : ""
 </script>
 
 {#if type === "options"}

packages/builder/src/components/backend/DataTable/Table.svelte

@@ -129,7 +129,7 @@
         bind:selectedRows
         allowSelectRows={allowEditing && !isUsersTable}
         allowEditRows={allowEditing}
-        allowEditColumns={allowEditing && isInternal}
+        allowEditColumns={allowEditing}
         showAutoColumns={!hideAutocolumns}
         on:editcolumn={e => editColumn(e.detail)}
         on:editrow={e => editRow(e.detail)}

packages/builder/src/components/backend/DataTable/buttons/ExistingRelationshipButton.svelte

@@ -0,0 +1,54 @@
+<script>
+  import { ActionButton, Modal, notifications } from "@budibase/bbui"
+  import CreateEditRelationship from "../../Datasources/CreateEditRelationship.svelte"
+  import { datasources, tables } from "../../../../stores/backend"
+  import { createEventDispatcher } from "svelte"
+
+  export let table
+  const dispatch = createEventDispatcher()
+
+  $: plusTables = datasource?.plus
+    ? Object.values(datasource?.entities || {})
+    : []
+  $: datasource = $datasources.list.find(
+    source => source._id === table?.sourceId
+  )
+
+  let modal
+
+  async function saveRelationship() {
+    try {
+      // Create datasource
+      await datasources.save(datasource)
+      notifications.success(`Relationship information saved.`)
+      const tableList = await tables.fetch()
+      await tables.select(tableList.find(tbl => tbl._id === table._id))
+      dispatch("updatecolumns")
+    } catch (err) {
+      notifications.error(`Error saving relationship info: ${err}`)
+    }
+  }
+</script>
+
+{#if table.sourceId}
+  <div>
+    <ActionButton
+      icon="DataCorrelated"
+      primary
+      size="S"
+      quiet
+      on:click={modal.show}
+    >
+      Define existing relationship
+    </ActionButton>
+  </div>
+  <Modal bind:this={modal}>
+    <CreateEditRelationship
+      {datasource}
+      save={saveRelationship}
+      close={modal.hide}
+      {plusTables}
+      selectedFromTable={table}
+    />
+  </Modal>
+{/if}

packages/builder/src/components/backend/DataTable/modals/CreateEditColumn.svelte

@@ -31,6 +31,9 @@
   const AUTO_TYPE = "auto"
   const FORMULA_TYPE = FIELDS.FORMULA.type
   const LINK_TYPE = FIELDS.LINK.type
+  const STRING_TYPE = FIELDS.STRING.type
+  const NUMBER_TYPE = FIELDS.NUMBER.type
+
   const dispatch = createEventDispatcher()
   const PROHIBITED_COLUMN_NAMES = ["type", "_id", "_rev", "tableId"]
   const { hide } = getContext(Context.Modal)
@@ -55,8 +58,9 @@
   let confirmDeleteDialog
   let deletion
 
+  $: checkConstraints(field)
   $: tableOptions = $tables.list.filter(
-    table => table._id !== $tables.draft._id && table.type !== "external"
+    opt => opt._id !== $tables.draft._id && opt.type === table.type
   )
   $: required = !!field?.constraints?.presence || primaryDisplay
   $: uneditable =
@@ -83,6 +87,7 @@
   $: canBeRequired =
     field.type !== LINK_TYPE && !uneditable && field.type !== AUTO_TYPE
   $: relationshipOptions = getRelationshipOptions(field)
+  $: external = table.type === "external"
 
   async function saveColumn() {
     if (field.type === AUTO_TYPE) {
@@ -193,6 +198,45 @@
       },
     ]
   }
+
+  function getAllowedTypes() {
+    if (!external) {
+      return [
+        ...Object.values(fieldDefinitions),
+        { name: "Auto Column", type: AUTO_TYPE },
+      ]
+    } else {
+      return [
+        FIELDS.STRING,
+        FIELDS.LONGFORM,
+        FIELDS.OPTIONS,
+        FIELDS.DATETIME,
+        FIELDS.NUMBER,
+        FIELDS.BOOLEAN,
+        FIELDS.ARRAY,
+        FIELDS.FORMULA,
+        FIELDS.LINK,
+      ]
+    }
+  }
+
+  function checkConstraints(fieldToCheck) {
+    // most types need this, just make sure its always present
+    if (fieldToCheck && !fieldToCheck.constraints) {
+      fieldToCheck.constraints = {}
+    }
+    // some string types may have been built by server, may not always have constraints
+    if (fieldToCheck.type === STRING_TYPE && !fieldToCheck.constraints.length) {
+      fieldToCheck.constraints.length = {}
+    }
+    // some number types made server-side will be missing constraints
+    if (
+      fieldToCheck.type === NUMBER_TYPE &&
+      !fieldToCheck.constraints.numericality
+    ) {
+      fieldToCheck.constraints.numericality = {}
+    }
+  }
 </script>
 
 <ModalContent
@@ -215,10 +259,7 @@
     label="Type"
     bind:value={field.type}
     on:change={handleTypeChange}
-    options={[
-      ...Object.values(fieldDefinitions),
-      { name: "Auto Column", type: AUTO_TYPE },
-    ]}
+    options={getAllowedTypes()}
     getOptionLabel={field => field.name}
     getOptionValue={field => field.type}
   />
@@ -245,7 +286,7 @@
     </div>
   {/if}
 
-  {#if canBeSearched}
+  {#if canBeSearched && !external}
     <div>
       <Label grey small>Search Indexes</Label>
       <Toggle

packages/builder/src/components/backend/Datasources/CreateEditRelationship.svelte

@@ -18,10 +18,19 @@
   export let fromRelationship = {}
   export let toRelationship = {}
   export let close
+  export let selectedFromTable
 
   let originalFromName = fromRelationship.name,
     originalToName = toRelationship.name
 
+  if (fromRelationship && !fromRelationship.relationshipType) {
+    fromRelationship.relationshipType = RelationshipTypes.MANY_TO_ONE
+  }
+
+  if (toRelationship && selectedFromTable) {
+    toRelationship.tableId = selectedFromTable._id
+  }
+
   function inSchema(table, prop, ogName) {
     if (!table || !prop || prop === ogName) {
       return false
@@ -114,6 +123,7 @@
     },
   ]
   $: updateRelationshipType(fromRelationship?.relationshipType)
+  $: tableChanged(fromTable, toTable)
 
   function updateRelationshipType(fromType) {
     if (fromType === RelationshipTypes.MANY_TO_MANY) {
@@ -205,7 +215,6 @@
     originalToName = toRelationship.name
     originalFromName = fromRelationship.name
     await save()
-    await tables.fetch()
   }
 
   async function deleteRelationship() {
@@ -215,10 +224,26 @@
     await tables.fetch()
     close()
   }
+
+  function tableChanged(fromTbl, toTbl) {
+    fromRelationship.name = toTbl?.name || ""
+    errors.fromCol = ""
+    toRelationship.name = fromTbl?.name || ""
+    errors.toCol = ""
+    if (toTbl || fromTbl) {
+      checkForErrors(
+        fromTable,
+        toTable,
+        through,
+        fromRelationship,
+        toRelationship
+      )
+    }
+  }
 </script>
 
 <ModalContent
-  title="Create Relationship"
+  title="Define Relationship"
   confirmText="Save"
   onConfirm={saveRelationship}
   disabled={!valid}
@@ -234,6 +259,7 @@
   <Select
     label="Select from table"
     options={tableOptions}
+    disabled={!!selectedFromTable}
     on:change={() => ($touched.from = true)}
     bind:error={errors.from}
     bind:value={toRelationship.tableId}

packages/builder/src/components/backend/TableNavigator/popovers/EditTablePopover.svelte

@@ -1,7 +1,7 @@
 <script>
   import { goto } from "@roxi/routify"
   import { allScreens, store } from "builderStore"
-  import { tables } from "stores/backend"
+  import { tables, datasources } from "stores/backend"
   import {
     ActionMenu,
     Icon,
@@ -40,7 +40,10 @@
     store.actions.screens.delete(templateScreens)
     await tables.fetch()
     notifications.success("Table deleted")
-    if (wasSelectedTable._id === table._id) {
+    if (table.type === "external") {
+      await datasources.fetch()
+    }
+    if (wasSelectedTable && wasSelectedTable._id === table._id) {
       $goto("./table")
     }
   }
@@ -64,9 +67,7 @@
     <Icon s hoverable name="MoreSmallList" />
   </div>
   <MenuItem icon="Edit" on:click={editorModal.show}>Edit</MenuItem>
-  {#if !external}
   <MenuItem icon="Delete" on:click={showDeleteModal}>Delete</MenuItem>
-  {/if}
 </ActionMenu>
 
 <Modal bind:this={editorModal}>

packages/builder/src/pages/builder/app/[application]/data/datasource/[selectedDatasource]/index.svelte

@@ -8,17 +8,18 @@
     Layout,
     Modal,
     InlineAlert,
+    ActionButton,
   } from "@budibase/bbui"
   import { datasources, integrations, queries, tables } from "stores/backend"
   import { notifications } from "@budibase/bbui"
   import IntegrationConfigForm from "components/backend/DatasourceNavigator/TableIntegrationMenu/IntegrationConfigForm.svelte"
-  import CreateEditRelationship from "./CreateEditRelationship/CreateEditRelationship.svelte"
-  import DisplayColumnModal from "./modals/EditDisplayColumnsModal.svelte"
+  import CreateEditRelationship from "components/backend/Datasources/CreateEditRelationship.svelte"
+  import CreateExternalTableModal from "./modals/CreateExternalTableModal.svelte"
   import ICONS from "components/backend/DatasourceNavigator/icons"
   import { capitalise } from "helpers"
 
   let relationshipModal
-  let displayColumnModal
+  let createExternalTableModal
   let selectedFromRelationship, selectedToRelationship
 
   $: datasource = $datasources.list.find(ds => ds._id === $datasources.selected)
@@ -110,8 +111,8 @@
     relationshipModal.show()
   }
 
-  function openDisplayColumnModal() {
-    displayColumnModal.show()
+  function createNewTable() {
+    createExternalTableModal.show()
   }
 </script>
 
@@ -126,8 +127,8 @@
   />
 </Modal>
 
-<Modal bind:this={displayColumnModal}>
-  <DisplayColumnModal {datasource} {plusTables} save={saveDatasource} />
+<Modal bind:this={createExternalTableModal}>
+  <CreateExternalTableModal {datasource} />
 </Modal>
 
 {#if datasource && integration}
@@ -163,15 +164,15 @@
         <div class="query-header">
           <Heading size="S">Tables</Heading>
           <div class="table-buttons">
-            {#if plusTables && plusTables.length !== 0}
-              <Button primary on:click={openDisplayColumnModal}>
-                Update display columns
-              </Button>
-            {/if}
             <div>
-              <Button primary on:click={updateDatasourceSchema}>
+              <ActionButton
+                size="S"
+                quiet
+                icon="DataRefresh"
+                on:click={updateDatasourceSchema}
+              >
                 Fetch tables from database
-              </Button>
+              </ActionButton>
             </div>
           </div>
         </div>
@@ -196,14 +197,23 @@
               <p>→</p>
             </div>
           {/each}
+          <div class="add-table">
+            <Button cta on:click={createNewTable}>Create new table</Button>
+          </div>
         </div>
         {#if plusTables?.length !== 0}
           <Divider />
           <div class="query-header">
             <Heading size="S">Relationships</Heading>
-            <Button primary on:click={() => openRelationshipModal()}
-              >Create relationship</Button
+            <ActionButton
+              icon="DataCorrelated"
+              primary
+              size="S"
+              quiet
+              on:click={openRelationshipModal}
             >
+              Define existing relationship
+            </ActionButton>
           </div>
           <Body>
             Tell budibase how your tables are related to get even more smart
@@ -318,11 +328,14 @@
 
   .table-buttons {
     display: grid;
-    grid-gap: var(--spacing-l);
     grid-template-columns: 1fr 1fr;
   }
 
   .table-buttons div {
     grid-column-end: -1;
   }
+
+  .add-table {
+    margin-top: var(--spacing-m);
+  }
 </style>

packages/builder/src/pages/builder/app/[application]/data/datasource/[selectedDatasource]/modals/CreateExternalTableModal.svelte

@@ -0,0 +1,45 @@
+<script>
+  import { ModalContent, Body, Input } from "@budibase/bbui"
+  import { tables, datasources } from "stores/backend"
+  import { goto } from "@roxi/routify"
+
+  export let datasource
+
+  let name = ""
+  $: valid = name && name.length > 0 && !datasource?.entities[name]
+  $: error =
+    name && datasource?.entities[name] ? "Table name already in use." : null
+
+  function buildDefaultTable(tableName, datasourceId) {
+    return {
+      name: tableName,
+      type: "external",
+      primary: ["id"],
+      sourceId: datasourceId,
+      schema: {
+        id: {
+          autocolumn: true,
+          type: "number",
+        },
+      },
+    }
+  }
+
+  async function saveTable() {
+    const table = await tables.save(buildDefaultTable(name, datasource._id))
+    await datasources.fetch()
+    $goto(`../../table/${table._id}`)
+  }
+</script>
+
+<ModalContent
+  title="Create new table"
+  confirmText="Create"
+  onConfirm={saveTable}
+  disabled={!valid}
+>
+  <Body
+    >Provide a name for your new table; you can add columns once it is created.</Body
+  >
+  <Input label="Table Name" bind:error bind:value={name} />
+</ModalContent>

packages/builder/src/pages/builder/app/[application]/data/datasource/[selectedDatasource]/modals/EditDisplayColumnsModal.svelte

@@ -1,43 +0,0 @@
-<script>
-  import { ModalContent, Select, Body } from "@budibase/bbui"
-  import { tables } from "stores/backend"
-
-  export let datasource
-  export let plusTables
-  export let save
-
-  async function saveDisplayColumns() {
-    // be explicit about copying over
-    for (let table of plusTables) {
-      datasource.entities[table.name].primaryDisplay = table.primaryDisplay
-    }
-    save()
-    await tables.fetch()
-  }
-
-  function getColumnOptions(table) {
-    if (!table || !table.schema) {
-      return []
-    }
-    return Object.entries(table.schema)
-      .filter(field => field[1].type !== "link")
-      .map(([fieldName]) => fieldName)
-  }
-</script>
-
-<ModalContent
-  title="Edit display columns"
-  confirmText="Save"
-  onConfirm={saveDisplayColumns}
->
-  <Body
-    >Select the columns that will be shown when displaying relationships.</Body
-  >
-  {#each plusTables as table}
-    <Select
-      label={table.name}
-      options={getColumnOptions(table)}
-      bind:value={table.primaryDisplay}
-    />
-  {/each}
-</ModalContent>

packages/builder/src/stores/backend/tables.js

@@ -11,6 +11,7 @@ export function createTablesStore() {
     const tablesResponse = await api.get(`/api/tables`)
     const tables = await tablesResponse.json()
     update(state => ({ ...state, list: tables }))
+    return tables
   }
 
   async function select(table) {
@@ -62,6 +63,9 @@ export function createTablesStore() {
     const response = await api.post(`/api/tables`, updatedTable)
     const savedTable = await response.json()
     await fetch()
+    if (table.type === "external") {
+      await datasources.fetch()
+    }
     await select(savedTable)
     return savedTable
   }

packages/server/src/api/controllers/datasource.js

@@ -9,7 +9,7 @@ const {
 } = require("../../db/utils")
 const { BuildSchemaErrors } = require("../../constants")
 const { integrations } = require("../../integrations")
-const { makeExternalQuery } = require("./row/utils")
+const { getDatasourceAndQuery } = require("./row/utils")
 
 exports.fetch = async function (ctx) {
   const database = new CouchDB(ctx.appId)
@@ -138,7 +138,7 @@ exports.find = async function (ctx) {
 exports.query = async function (ctx) {
   const queryJson = ctx.request.body
   try {
-    ctx.body = await makeExternalQuery(ctx.appId, queryJson)
+    ctx.body = await getDatasourceAndQuery(ctx.appId, queryJson)
   } catch (err) {
     ctx.throw(400, err)
   }
@@ -152,6 +152,19 @@ const buildSchemaHelper = async datasource => {
   await connector.buildSchema(datasource._id, datasource.entities)
   datasource.entities = connector.tables
 
+  // make sure they all have a display name selected
+  for (let entity of Object.values(datasource.entities)) {
+    if (entity.primaryDisplay) {
+      continue
+    }
+    const notAutoColumn = Object.values(entity.schema).find(
+      schema => !schema.autocolumn
+    )
+    if (notAutoColumn) {
+      entity.primaryDisplay = notAutoColumn.name
+    }
+  }
+
   const errors = connector.schemaErrors
   let error = null
   if (errors && Object.keys(errors).length > 0) {

packages/server/src/api/controllers/row/ExternalRequest.ts

@@ -36,7 +36,7 @@ interface RunConfig {
 }
 
 module External {
-  const { makeExternalQuery } = require("./utils")
+  const { getDatasourceAndQuery } = require("./utils")
   const {
     DataSourceOperation,
     FieldTypes,
@@ -46,6 +46,7 @@ module External {
   const { processObjectSync } = require("@budibase/string-templates")
   const { cloneDeep } = require("lodash/fp")
   const CouchDB = require("../../../db")
+  const { processFormulas } = require("../../../utilities/rowProcessor/utils")
 
   function buildFilters(
     id: string | undefined,
@@ -225,7 +226,7 @@ module External {
         manyRelationships: ManyRelationship[] = []
       for (let [key, field] of Object.entries(table.schema)) {
         // if set already, or not set just skip it
-        if ((!row[key] && row[key] !== "") || newRow[key] || field.autocolumn) {
+        if (row[key] == null || newRow[key] || field.autocolumn || field.type === FieldTypes.FORMULA) {
           continue
         }
         // if its an empty string then it means return the column to null (if possible)
@@ -361,7 +362,7 @@ module External {
           relationships
         )
       }
-      return Object.values(finalRows)
+      return processFormulas(table, Object.values(finalRows))
     }
 
     /**
@@ -428,7 +429,7 @@ module External {
         const tableId = isMany ? field.through : field.tableId
         const manyKey = field.throughFrom || primaryKey
         const fieldName = isMany ? manyKey : field.fieldName
-        const response = await makeExternalQuery(this.appId, {
+        const response = await getDatasourceAndQuery(this.appId, {
           endpoint: getEndpoint(tableId, DataSourceOperation.READ),
           filters: {
             equal: {
@@ -479,7 +480,7 @@ module External {
           : DataSourceOperation.CREATE
         if (!found) {
           promises.push(
-            makeExternalQuery(appId, {
+            getDatasourceAndQuery(appId, {
               endpoint: getEndpoint(tableId, operation),
               // if we're doing many relationships then we're writing, only one response
               body,
@@ -509,7 +510,7 @@ module External {
               : DataSourceOperation.UPDATE
             const body = isMany ? null : { [colName]: null }
             promises.push(
-              makeExternalQuery(this.appId, {
+              getDatasourceAndQuery(this.appId, {
                 endpoint: getEndpoint(tableId, op),
                 body,
                 filters,
@@ -532,16 +533,17 @@ module External {
       table: Table,
       includeRelations: IncludeRelationships = IncludeRelationships.INCLUDE
     ) {
-      function extractNonLinkFieldNames(table: Table, existing: string[] = []) {
+      function extractRealFields(table: Table, existing: string[] = []) {
         return Object.entries(table.schema)
           .filter(
             column =>
               column[1].type !== FieldTypes.LINK &&
+              column[1].type !== FieldTypes.FORMULA &&
               !existing.find((field: string) => field === column[0])
           )
           .map(column => `${table.name}.${column[0]}`)
       }
-      let fields = extractNonLinkFieldNames(table)
+      let fields = extractRealFields(table)
       for (let field of Object.values(table.schema)) {
         if (field.type !== FieldTypes.LINK || !includeRelations) {
           continue
@@ -549,7 +551,7 @@ module External {
         const { tableName: linkTableName } = breakExternalTableId(field.tableId)
         const linkTable = this.tables[linkTableName]
         if (linkTable) {
-          const linkedFields = extractNonLinkFieldNames(linkTable, fields)
+          const linkedFields = extractRealFields(linkTable, fields)
           fields = fields.concat(linkedFields)
         }
       }
@@ -609,7 +611,7 @@ module External {
         },
       }
       // can't really use response right now
-      const response = await makeExternalQuery(appId, json)
+      const response = await getDatasourceAndQuery(appId, json)
       // handle many to many relationships now if we know the ID (could be auto increment)
       if (
         operation !== DataSourceOperation.READ &&

packages/server/src/api/controllers/row/utils.js

@@ -4,8 +4,8 @@ const CouchDB = require("../../../db")
 const { InternalTables } = require("../../../db/utils")
 const userController = require("../user")
 const { FieldTypes } = require("../../../constants")
-const { integrations } = require("../../../integrations")
 const { processStringSync } = require("@budibase/string-templates")
+const { makeExternalQuery } = require("../../../integrations/base/utils")
 
 validateJs.extend(validateJs.validators.datetime, {
   parse: function (value) {
@@ -17,18 +17,11 @@ validateJs.extend(validateJs.validators.datetime, {
   },
 })
 
-exports.makeExternalQuery = async (appId, json) => {
+exports.getDatasourceAndQuery = async (appId, json) => {
   const datasourceId = json.endpoint.datasourceId
   const db = new CouchDB(appId)
   const datasource = await db.get(datasourceId)
-  const Integration = integrations[datasource.source]
-  // query is the opinionated function
-  if (Integration.prototype.query) {
-    const integration = new Integration(datasource.config)
-    return integration.query(json)
-  } else {
-    throw "Datasource does not support query."
-  }
+  return makeExternalQuery(datasource, json)
 }
 
 exports.findRow = async (ctx, db, tableId, rowId) => {

packages/server/src/api/controllers/table/external.js

@@ -0,0 +1,276 @@
+const CouchDB = require("../../../db")
+const {
+  buildExternalTableId,
+  breakExternalTableId,
+} = require("../../../integrations/utils")
+const {
+  getTable,
+  generateForeignKey,
+  generateJunctionTableName,
+  foreignKeyStructure,
+} = require("./utils")
+const {
+  DataSourceOperation,
+  FieldTypes,
+  RelationshipTypes,
+} = require("../../../constants")
+const { makeExternalQuery } = require("../../../integrations/base/utils")
+const { cloneDeep } = require("lodash/fp")
+
+async function makeTableRequest(
+  datasource,
+  operation,
+  table,
+  tables,
+  oldTable = null
+) {
+  const json = {
+    endpoint: {
+      datasourceId: datasource._id,
+      entityId: table._id,
+      operation,
+    },
+    meta: {
+      tables,
+    },
+    table,
+  }
+  if (oldTable) {
+    json.meta.table = oldTable
+  }
+  return makeExternalQuery(datasource, json)
+}
+
+function cleanupRelationships(table, tables, oldTable = null) {
+  const tableToIterate = oldTable ? oldTable : table
+  // clean up relationships in couch table schemas
+  for (let [key, schema] of Object.entries(tableToIterate.schema)) {
+    if (
+      schema.type === FieldTypes.LINK &&
+      (!oldTable || table.schema[key] == null)
+    ) {
+      const relatedTable = Object.values(tables).find(
+        table => table._id === schema.tableId
+      )
+      const foreignKey = schema.foreignKey
+      if (!relatedTable || !foreignKey) {
+        continue
+      }
+      for (let [relatedKey, relatedSchema] of Object.entries(
+        relatedTable.schema
+      )) {
+        if (
+          relatedSchema.type === FieldTypes.LINK &&
+          relatedSchema.fieldName === foreignKey
+        ) {
+          delete relatedTable.schema[relatedKey]
+        }
+      }
+    }
+  }
+}
+
+function getDatasourceId(table) {
+  if (!table) {
+    throw "No table supplied"
+  }
+  if (table.sourceId) {
+    return table.sourceId
+  }
+  return breakExternalTableId(table._id).datasourceId
+}
+
+function otherRelationshipType(type) {
+  if (type === RelationshipTypes.MANY_TO_MANY) {
+    return RelationshipTypes.MANY_TO_MANY
+  }
+  return type === RelationshipTypes.ONE_TO_MANY
+    ? RelationshipTypes.MANY_TO_ONE
+    : RelationshipTypes.ONE_TO_MANY
+}
+
+function generateManyLinkSchema(datasource, column, table, relatedTable) {
+  const primary = table.name + table.primary[0]
+  const relatedPrimary = relatedTable.name + relatedTable.primary[0]
+  const jcTblName = generateJunctionTableName(column, table, relatedTable)
+  // first create the new table
+  const junctionTable = {
+    _id: buildExternalTableId(datasource._id, jcTblName),
+    name: jcTblName,
+    primary: [primary, relatedPrimary],
+    constrained: [primary, relatedPrimary],
+    schema: {
+      [primary]: foreignKeyStructure(primary, {
+        toTable: table.name,
+        toKey: table.primary[0],
+      }),
+      [relatedPrimary]: foreignKeyStructure(relatedPrimary, {
+        toTable: relatedTable.name,
+        toKey: relatedTable.primary[0],
+      }),
+    },
+  }
+  column.through = junctionTable._id
+  column.throughFrom = primary
+  column.throughTo = relatedPrimary
+  column.fieldName = relatedPrimary
+  return junctionTable
+}
+
+function generateLinkSchema(column, table, relatedTable, type) {
+  const isOneSide = type === RelationshipTypes.ONE_TO_MANY
+  const primary = isOneSide ? relatedTable.primary[0] : table.primary[0]
+  // generate a foreign key
+  const foreignKey = generateForeignKey(column, relatedTable)
+  column.relationshipType = type
+  column.foreignKey = isOneSide ? foreignKey : primary
+  column.fieldName = isOneSide ? primary : foreignKey
+  return foreignKey
+}
+
+function generateRelatedSchema(linkColumn, table, relatedTable, columnName) {
+  // generate column for other table
+  const relatedSchema = cloneDeep(linkColumn)
+  // swap them from the main link
+  if (linkColumn.foreignKey) {
+    relatedSchema.fieldName = linkColumn.foreignKey
+    relatedSchema.foreignKey = linkColumn.fieldName
+  }
+  // is many to many
+  else {
+    // don't need to copy through, already got it
+    relatedSchema.fieldName = linkColumn.throughFrom
+    relatedSchema.throughTo = linkColumn.throughFrom
+    relatedSchema.throughFrom = linkColumn.throughTo
+  }
+  relatedSchema.relationshipType = otherRelationshipType(
+    linkColumn.relationshipType
+  )
+  relatedSchema.tableId = relatedTable._id
+  relatedSchema.name = columnName
+  table.schema[columnName] = relatedSchema
+}
+
+function isRelationshipSetup(column) {
+  return column.foreignKey || column.through
+}
+
+exports.save = async function (ctx) {
+  const appId = ctx.appId
+  const table = ctx.request.body
+  // can't do this
+  delete table.dataImport
+  const datasourceId = getDatasourceId(ctx.request.body)
+  let tableToSave = {
+    type: "table",
+    _id: buildExternalTableId(datasourceId, table.name),
+    ...table,
+  }
+
+  let oldTable
+  if (ctx.request.body && ctx.request.body._id) {
+    oldTable = await getTable(appId, ctx.request.body._id)
+  }
+
+  const db = new CouchDB(appId)
+  const datasource = await db.get(datasourceId)
+  const oldTables = cloneDeep(datasource.entities)
+  const tables = datasource.entities
+
+  const extraTablesToUpdate = []
+
+  // check if relations need setup
+  for (let schema of Object.values(tableToSave.schema)) {
+    if (schema.type !== FieldTypes.LINK || isRelationshipSetup(schema)) {
+      continue
+    }
+    const relatedTable = Object.values(tables).find(
+      table => table._id === schema.tableId
+    )
+    const relatedColumnName = schema.fieldName
+    const relationType = schema.relationshipType
+    if (relationType === RelationshipTypes.MANY_TO_MANY) {
+      const junctionTable = generateManyLinkSchema(
+        datasource,
+        schema,
+        table,
+        relatedTable
+      )
+      if (tables[junctionTable.name]) {
+        throw "Junction table already exists, cannot create another relationship."
+      }
+      tables[junctionTable.name] = junctionTable
+      extraTablesToUpdate.push(junctionTable)
+    } else {
+      const fkTable =
+        relationType === RelationshipTypes.ONE_TO_MANY ? table : relatedTable
+      const foreignKey = generateLinkSchema(
+        schema,
+        table,
+        relatedTable,
+        relationType
+      )
+      fkTable.schema[foreignKey] = foreignKeyStructure(foreignKey)
+      if (fkTable.constrained == null) {
+        fkTable.constrained = []
+      }
+      if (fkTable.constrained.indexOf(foreignKey) === -1) {
+        fkTable.constrained.push(foreignKey)
+      }
+      // foreign key is in other table, need to save it to external
+      if (fkTable._id !== table._id) {
+        extraTablesToUpdate.push(fkTable)
+      }
+    }
+    generateRelatedSchema(schema, relatedTable, table, relatedColumnName)
+    schema.main = true
+  }
+
+  cleanupRelationships(tableToSave, tables, oldTable)
+
+  const operation = oldTable
+    ? DataSourceOperation.UPDATE_TABLE
+    : DataSourceOperation.CREATE_TABLE
+  await makeTableRequest(datasource, operation, tableToSave, tables, oldTable)
+  // update any extra tables (like foreign keys in other tables)
+  for (let extraTable of extraTablesToUpdate) {
+    const oldExtraTable = oldTables[extraTable.name]
+    let op = oldExtraTable
+      ? DataSourceOperation.UPDATE_TABLE
+      : DataSourceOperation.CREATE_TABLE
+    await makeTableRequest(datasource, op, extraTable, tables, oldExtraTable)
+  }
+
+  // make sure the constrained list, all still exist
+  if (Array.isArray(tableToSave.constrained)) {
+    tableToSave.constrained = tableToSave.constrained.filter(constraint =>
+      Object.keys(tableToSave.schema).includes(constraint)
+    )
+  }
+
+  // store it into couch now for budibase reference
+  datasource.entities[tableToSave.name] = tableToSave
+  await db.put(datasource)
+
+  return tableToSave
+}
+
+exports.destroy = async function (ctx) {
+  const appId = ctx.appId
+  const tableToDelete = await getTable(appId, ctx.params.tableId)
+  const datasourceId = getDatasourceId(tableToDelete)
+
+  const db = new CouchDB(appId)
+  const datasource = await db.get(datasourceId)
+  const tables = datasource.entities
+
+  const operation = DataSourceOperation.DELETE_TABLE
+  await makeTableRequest(datasource, operation, tableToDelete, tables)
+
+  cleanupRelationships(tableToDelete, tables)
+
+  delete datasource.entities[tableToDelete.name]
+  await db.put(datasource)
+
+  return tableToDelete
+}

packages/server/src/api/controllers/table/index.js

@@ -1,16 +1,28 @@
 const CouchDB = require("../../../db")
-const linkRows = require("../../../db/linkedRows")
+const internal = require("./internal")
+const external = require("./external")
 const csvParser = require("../../../utilities/csvParser")
+const { isExternalTable } = require("../../../integrations/utils")
 const {
-  getRowParams,
   getTableParams,
-  generateTableID,
   getDatasourceParams,
   BudibaseInternalDB,
 } = require("../../../db/utils")
-const { FieldTypes } = require("../../../constants")
-const { TableSaveFunctions, getTable } = require("./utils")
+const { getTable } = require("./utils")
 
+function pickApi({ tableId, table }) {
+  if (table && !tableId) {
+    tableId = table._id
+  }
+  if (table && table.type === "external") {
+    return external
+  } else if (tableId && isExternalTable(tableId)) {
+    return external
+  }
+  return internal
+}
+
+// covers both internal and external
 exports.fetch = async function (ctx) {
   const db = new CouchDB(ctx.appId)
 
@@ -50,143 +62,23 @@ exports.find = async function (ctx) {
 
 exports.save = async function (ctx) {
   const appId = ctx.appId
-  const db = new CouchDB(appId)
-  const { dataImport, ...rest } = ctx.request.body
-  let tableToSave = {
-    type: "table",
-    _id: generateTableID(),
-    views: {},
-    ...rest,
-  }
-
-  // if the table obj had an _id then it will have been retrieved
-  let oldTable
-  if (ctx.request.body && ctx.request.body._id) {
-    oldTable = await db.get(ctx.request.body._id)
-  }
-
-  // saving a table is a complex operation, involving many different steps, this
-  // has been broken out into a utility to make it more obvious/easier to manipulate
-  const tableSaveFunctions = new TableSaveFunctions({
-    db,
-    ctx,
-    oldTable,
-    dataImport,
-  })
-  tableToSave = await tableSaveFunctions.before(tableToSave)
-
-  // make sure that types don't change of a column, have to remove
-  // the column if you want to change the type
-  if (oldTable && oldTable.schema) {
-    for (let propKey of Object.keys(tableToSave.schema)) {
-      let column = tableToSave.schema[propKey]
-      let oldColumn = oldTable.schema[propKey]
-      if (oldColumn && oldColumn.type === "internal") {
-        oldColumn.type = "auto"
-      }
-      if (oldColumn && oldColumn.type !== column.type) {
-        ctx.throw(400, "Cannot change the type of a column")
-      }
-    }
-  }
-
-  // Don't rename if the name is the same
-  let { _rename } = tableToSave
-  /* istanbul ignore next */
-  if (_rename && _rename.old === _rename.updated) {
-    _rename = null
-    delete tableToSave._rename
-  }
-
-  // rename row fields when table column is renamed
-  /* istanbul ignore next */
-  if (_rename && tableToSave.schema[_rename.updated].type === FieldTypes.LINK) {
-    ctx.throw(400, "Cannot rename a linked column.")
-  }
-
-  tableToSave = await tableSaveFunctions.mid(tableToSave)
-
-  // update schema of non-statistics views when new columns are added
-  for (let view in tableToSave.views) {
-    const tableView = tableToSave.views[view]
-    if (!tableView) continue
-
-    if (tableView.schema.group || tableView.schema.field) continue
-    tableView.schema = tableToSave.schema
-  }
-
-  // update linked rows
-  try {
-    const linkResp = await linkRows.updateLinks({
-      appId,
-      eventType: oldTable
-        ? linkRows.EventType.TABLE_UPDATED
-        : linkRows.EventType.TABLE_SAVE,
-      table: tableToSave,
-      oldTable: oldTable,
-    })
-    if (linkResp != null && linkResp._rev) {
-      tableToSave._rev = linkResp._rev
-    }
-  } catch (err) {
-    ctx.throw(400, err)
-  }
-
-  // don't perform any updates until relationships have been
-  // checked by the updateLinks function
-  const updatedRows = tableSaveFunctions.getUpdatedRows()
-  if (updatedRows && updatedRows.length !== 0) {
-    await db.bulkDocs(updatedRows)
-  }
-  const result = await db.put(tableToSave)
-  tableToSave._rev = result.rev
-
-  tableToSave = await tableSaveFunctions.after(tableToSave)
-
-  ctx.eventEmitter &&
-    ctx.eventEmitter.emitTable(`table:save`, appId, tableToSave)
-
+  const table = ctx.request.body
+  const savedTable = await pickApi({ table }).save(ctx)
   ctx.status = 200
-  ctx.message = `Table ${ctx.request.body.name} saved successfully.`
-  ctx.body = tableToSave
+  ctx.message = `Table ${table.name} saved successfully.`
+  ctx.eventEmitter &&
+    ctx.eventEmitter.emitTable(`table:save`, appId, savedTable)
+  ctx.body = savedTable
 }
 
 exports.destroy = async function (ctx) {
   const appId = ctx.appId
-  const db = new CouchDB(appId)
-  const tableToDelete = await db.get(ctx.params.tableId)
-
-  // Delete all rows for that table
-  const rows = await db.allDocs(
-    getRowParams(ctx.params.tableId, null, {
-      include_docs: true,
-    })
-  )
-  await db.bulkDocs(rows.rows.map(row => ({ ...row.doc, _deleted: true })))
-
-  // update linked rows
-  await linkRows.updateLinks({
-    appId,
-    eventType: linkRows.EventType.TABLE_DELETE,
-    table: tableToDelete,
-  })
-
-  // don't remove the table itself until very end
-  await db.remove(tableToDelete)
-
-  // remove table search index
-  const currentIndexes = await db.getIndexes()
-  const existingIndex = currentIndexes.indexes.find(
-    existing => existing.name === `search:${ctx.params.tableId}`
-  )
-  if (existingIndex) {
-    await db.deleteIndex(existingIndex)
-  }
-
+  const tableId = ctx.params.tableId
+  const deletedTable = await pickApi({ tableId }).destroy(ctx)
   ctx.eventEmitter &&
-    ctx.eventEmitter.emitTable(`table:delete`, appId, tableToDelete)
+    ctx.eventEmitter.emitTable(`table:delete`, appId, deletedTable)
   ctx.status = 200
-  ctx.body = { message: `Table ${ctx.params.tableId} deleted.` }
+  ctx.body = { message: `Table ${tableId} deleted.` }
 }
 
 exports.validateCSVSchema = async function (ctx) {

packages/server/src/api/controllers/table/internal.js

@@ -0,0 +1,138 @@
+const CouchDB = require("../../../db")
+const linkRows = require("../../../db/linkedRows")
+const { getRowParams, generateTableID } = require("../../../db/utils")
+const { FieldTypes } = require("../../../constants")
+const { TableSaveFunctions } = require("./utils")
+
+exports.save = async function (ctx) {
+  const appId = ctx.appId
+  const db = new CouchDB(appId)
+  const { dataImport, ...rest } = ctx.request.body
+  let tableToSave = {
+    type: "table",
+    _id: generateTableID(),
+    views: {},
+    ...rest,
+  }
+
+  // if the table obj had an _id then it will have been retrieved
+  let oldTable
+  if (ctx.request.body && ctx.request.body._id) {
+    oldTable = await db.get(ctx.request.body._id)
+  }
+
+  // saving a table is a complex operation, involving many different steps, this
+  // has been broken out into a utility to make it more obvious/easier to manipulate
+  const tableSaveFunctions = new TableSaveFunctions({
+    db,
+    ctx,
+    oldTable,
+    dataImport,
+  })
+  tableToSave = await tableSaveFunctions.before(tableToSave)
+
+  // make sure that types don't change of a column, have to remove
+  // the column if you want to change the type
+  if (oldTable && oldTable.schema) {
+    for (let propKey of Object.keys(tableToSave.schema)) {
+      let column = tableToSave.schema[propKey]
+      let oldColumn = oldTable.schema[propKey]
+      if (oldColumn && oldColumn.type === "internal") {
+        oldColumn.type = "auto"
+      }
+      if (oldColumn && oldColumn.type !== column.type) {
+        ctx.throw(400, "Cannot change the type of a column")
+      }
+    }
+  }
+
+  // Don't rename if the name is the same
+  let { _rename } = tableToSave
+  /* istanbul ignore next */
+  if (_rename && _rename.old === _rename.updated) {
+    _rename = null
+    delete tableToSave._rename
+  }
+
+  // rename row fields when table column is renamed
+  /* istanbul ignore next */
+  if (_rename && tableToSave.schema[_rename.updated].type === FieldTypes.LINK) {
+    ctx.throw(400, "Cannot rename a linked column.")
+  }
+
+  tableToSave = await tableSaveFunctions.mid(tableToSave)
+
+  // update schema of non-statistics views when new columns are added
+  for (let view in tableToSave.views) {
+    const tableView = tableToSave.views[view]
+    if (!tableView) continue
+
+    if (tableView.schema.group || tableView.schema.field) continue
+    tableView.schema = tableToSave.schema
+  }
+
+  // update linked rows
+  try {
+    const linkResp = await linkRows.updateLinks({
+      appId,
+      eventType: oldTable
+        ? linkRows.EventType.TABLE_UPDATED
+        : linkRows.EventType.TABLE_SAVE,
+      table: tableToSave,
+      oldTable: oldTable,
+    })
+    if (linkResp != null && linkResp._rev) {
+      tableToSave._rev = linkResp._rev
+    }
+  } catch (err) {
+    ctx.throw(400, err)
+  }
+
+  // don't perform any updates until relationships have been
+  // checked by the updateLinks function
+  const updatedRows = tableSaveFunctions.getUpdatedRows()
+  if (updatedRows && updatedRows.length !== 0) {
+    await db.bulkDocs(updatedRows)
+  }
+  const result = await db.put(tableToSave)
+  tableToSave._rev = result.rev
+
+  tableToSave = await tableSaveFunctions.after(tableToSave)
+
+  return tableToSave
+}
+
+exports.destroy = async function (ctx) {
+  const appId = ctx.appId
+  const db = new CouchDB(appId)
+  const tableToDelete = await db.get(ctx.params.tableId)
+
+  // Delete all rows for that table
+  const rows = await db.allDocs(
+    getRowParams(ctx.params.tableId, null, {
+      include_docs: true,
+    })
+  )
+  await db.bulkDocs(rows.rows.map(row => ({ ...row.doc, _deleted: true })))
+
+  // update linked rows
+  await linkRows.updateLinks({
+    appId,
+    eventType: linkRows.EventType.TABLE_DELETE,
+    table: tableToDelete,
+  })
+
+  // don't remove the table itself until very end
+  await db.remove(tableToDelete)
+
+  // remove table search index
+  const currentIndexes = await db.getIndexes()
+  const existingIndex = currentIndexes.indexes.find(
+    existing => existing.name === `search:${ctx.params.tableId}`
+  )
+  if (existingIndex) {
+    await db.deleteIndex(existingIndex)
+  }
+
+  return tableToDelete
+}

packages/server/src/api/controllers/table/utils.js

@@ -315,4 +315,24 @@ exports.checkForViewUpdates = async (db, table, rename, deletedColumns) => {
   }
 }
 
+exports.generateForeignKey = (column, relatedTable) => {
+  return `fk_${relatedTable.name}_${column.fieldName}`
+}
+
+exports.generateJunctionTableName = (column, table, relatedTable) => {
+  return `jt_${table.name}_${relatedTable.name}_${column.name}_${column.fieldName}`
+}
+
+exports.foreignKeyStructure = (keyName, meta = null) => {
+  const structure = {
+    type: FieldTypes.NUMBER,
+    constraints: {},
+    name: keyName,
+  }
+  if (meta) {
+    structure.meta = meta
+  }
+  return structure
+}
+
 exports.TableSaveFunctions = TableSaveFunctions

packages/server/src/constants/index.js

@@ -62,6 +62,9 @@ exports.DataSourceOperation = {
   READ: "READ",
   UPDATE: "UPDATE",
   DELETE: "DELETE",
+  CREATE_TABLE: "CREATE_TABLE",
+  UPDATE_TABLE: "UPDATE_TABLE",
+  DELETE_TABLE: "DELETE_TABLE",
 }
 
 exports.SortDirection = {

packages/server/src/definitions/common.ts

@@ -17,6 +17,11 @@ export interface FieldSchema {
   autocolumn?: boolean
   throughFrom?: string
   throughTo?: string
+  main?: boolean
+  meta?: {
+    toTable: string
+    toKey: string
+  }
   constraints?: {
     type?: string
     email?: boolean
@@ -36,11 +41,12 @@ export interface TableSchema {
 export interface Table extends Base {
   type?: string
   views?: {}
-  name?: string
+  name: string
   primary?: string[]
   schema: TableSchema
   primaryDisplay?: string
   sourceId?: string
+  constrained?: string[]
 }
 
 export interface Row extends Base {

packages/server/src/definitions/datasource.ts

@@ -5,6 +5,9 @@ export enum Operation {
   READ = "READ",
   UPDATE = "UPDATE",
   DELETE = "DELETE",
+  CREATE_TABLE = "CREATE_TABLE",
+  UPDATE_TABLE = "UPDATE_TABLE",
+  DELETE_TABLE = "DELETE_TABLE",
 }
 
 export enum SortDirection {
@@ -142,8 +145,10 @@ export interface QueryJson {
   sort?: SortJson
   paginate?: PaginationJson
   body?: object
+  table?: Table
   meta?: {
     table?: Table
+    tables?: Record<string, Table>
   }
   extra?: {
     idFilter?: SearchFilters

packages/server/src/integrations/base/sql.ts

@@ -1,19 +1,24 @@
 import { Knex, knex } from "knex"
-const BASE_LIMIT = 5000
 import {
-  QueryJson,
-  SearchFilters,
-  QueryOptions,
-  SortDirection,
   Operation,
+  QueryJson,
+  QueryOptions,
   RelationshipsJson,
+  SearchFilters,
+  SortDirection,
 } from "../../definitions/datasource"
 import { isIsoDateString } from "../utils"
+import SqlTableQueryBuilder from "./sqlTable"
+
+const BASE_LIMIT = 5000
 
 type KnexQuery = Knex.QueryBuilder | Knex
 
 function parseBody(body: any) {
   for (let [key, value] of Object.entries(body)) {
+    if (Array.isArray(value)) {
+      body[key] = JSON.stringify(value)
+    }
     if (typeof value !== "string") {
       continue
     }
@@ -243,23 +248,14 @@ function buildDelete(
   }
 }
 
-class SqlQueryBuilder {
-  private readonly sqlClient: string
+class SqlQueryBuilder extends SqlTableQueryBuilder {
   private readonly limit: number
   // pass through client to get flavour of SQL
   constructor(client: string, limit: number = BASE_LIMIT) {
-    this.sqlClient = client
+    super(client)
     this.limit = limit
   }
 
-  /**
-   * @param json the input JSON structure from which an SQL query will be built.
-   * @return {string} the operation that was found in the JSON.
-   */
-  _operation(json: QueryJson): Operation {
-    return json.endpoint.operation
-  }
-
   /**
    * @param json The JSON query DSL which is to be converted to SQL.
    * @param opts extra options which are to be passed into the query builder, e.g. disableReturning
@@ -267,7 +263,8 @@ class SqlQueryBuilder {
    * @return {{ sql: string, bindings: object }} the query ready to be passed to the driver.
    */
   _query(json: QueryJson, opts: QueryOptions = {}) {
-    const client = knex({ client: this.sqlClient })
+    const sqlClient = this.getSqlClient()
+    const client = knex({ client: sqlClient })
     let query
     switch (this._operation(json)) {
       case Operation.CREATE:
@@ -282,6 +279,8 @@ class SqlQueryBuilder {
       case Operation.DELETE:
         query = buildDelete(client, json, opts)
         break
+      case Operation.CREATE_TABLE: case Operation.UPDATE_TABLE: case Operation.DELETE_TABLE:
+        return this._tableQuery(json)
       default:
         throw `Operation type is not supported by SQL query builder`
     }

packages/server/src/integrations/base/sqlTable.ts

@@ -0,0 +1,167 @@
+import { Knex, knex } from "knex"
+import { Table } from "../../definitions/common"
+import { Operation, QueryJson } from "../../definitions/datasource"
+import { breakExternalTableId } from "../utils"
+import SchemaBuilder = Knex.SchemaBuilder
+import CreateTableBuilder = Knex.CreateTableBuilder
+const { FieldTypes, RelationshipTypes } = require("../../constants")
+
+function generateSchema(schema: CreateTableBuilder, table: Table, tables: Record<string, Table>, oldTable: null | Table = null) {
+  let primaryKey = table && table.primary ? table.primary[0] : null
+  const columns = Object.values(table.schema)
+  // all columns in a junction table will be meta
+  let metaCols = columns.filter(col => col.meta)
+  let isJunction = metaCols.length === columns.length
+  // can't change primary once its set for now
+  if (primaryKey && !oldTable && !isJunction) {
+    schema.increments(primaryKey).primary()
+  } else if (!oldTable && isJunction) {
+    schema.primary(metaCols.map(col => col.name))
+  }
+
+
+  // check if any columns need added
+  const foreignKeys = Object.values(table.schema).map(col => col.foreignKey)
+  for (let [key, column] of Object.entries(table.schema)) {
+    // skip things that are already correct
+    const oldColumn = oldTable ? oldTable.schema[key] : null
+    if ((oldColumn && oldColumn.type === column.type) || (primaryKey === key && !isJunction)) {
+      continue
+    }
+    switch (column.type) {
+      case FieldTypes.STRING: case FieldTypes.OPTIONS: case FieldTypes.LONGFORM:
+        schema.string(key)
+        break
+      case FieldTypes.NUMBER:
+        // if meta is specified then this is a junction table entry
+        if (column.meta && column.meta.toKey && column.meta.toTable) {
+          const { toKey, toTable } = column.meta
+          schema.integer(key).unsigned()
+          schema.foreign(key).references(`${toTable}.${toKey}`)
+        } else if (foreignKeys.indexOf(key) === -1) {
+          schema.float(key)
+        }
+        break
+      case FieldTypes.BOOLEAN:
+        schema.boolean(key)
+        break
+      case FieldTypes.DATETIME:
+        schema.datetime(key)
+        break
+      case FieldTypes.ARRAY:
+        schema.json(key)
+        break
+      case FieldTypes.LINK:
+        // this side of the relationship doesn't need any SQL work
+        if (
+          column.relationshipType !== RelationshipTypes.MANY_TO_ONE &&
+          column.relationshipType !== RelationshipTypes.MANY_TO_MANY
+        ) {
+          if (!column.foreignKey || !column.tableId) {
+            throw "Invalid relationship schema"
+          }
+          const { tableName } = breakExternalTableId(column.tableId)
+          // @ts-ignore
+          const relatedTable = tables[tableName]
+          if (!relatedTable) {
+            throw "Referenced table doesn't exist"
+          }
+          schema.integer(column.foreignKey).unsigned()
+          schema.foreign(column.foreignKey).references(`${tableName}.${relatedTable.primary[0]}`)
+        }
+        break
+    }
+  }
+
+  // need to check if any columns have been deleted
+  if (oldTable) {
+    const deletedColumns = Object.entries(oldTable.schema)
+      .filter(([key, schema]) => schema.type !== FieldTypes.LINK && table.schema[key] == null)
+      .map(([key]) => key)
+    deletedColumns.forEach(key => {
+      if (oldTable.constrained && oldTable.constrained.indexOf(key) !== -1) {
+        schema.dropForeign(key)
+      }
+      schema.dropColumn(key)
+    })
+  }
+
+  return schema
+}
+
+function buildCreateTable(
+  knex: Knex,
+  table: Table,
+  tables: Record<string, Table>,
+): SchemaBuilder {
+  return knex.schema.createTable(table.name, schema => {
+    generateSchema(schema, table, tables)
+  })
+}
+
+function buildUpdateTable(
+  knex: Knex,
+  table: Table,
+  tables: Record<string, Table>,
+  oldTable: Table,
+): SchemaBuilder {
+  return knex.schema.alterTable(table.name, schema => {
+    generateSchema(schema, table, tables, oldTable)
+  })
+}
+
+function buildDeleteTable(
+  knex: Knex,
+  table: Table,
+): SchemaBuilder {
+  return knex.schema.dropTable(table.name)
+}
+
+class SqlTableQueryBuilder {
+  private readonly sqlClient: string
+
+  // pass through client to get flavour of SQL
+  constructor(client: string) {
+    this.sqlClient = client
+  }
+
+  getSqlClient(): string {
+    return this.sqlClient
+  }
+
+  /**
+   * @param json the input JSON structure from which an SQL query will be built.
+   * @return {string} the operation that was found in the JSON.
+   */
+  _operation(json: QueryJson): Operation {
+    return json.endpoint.operation
+  }
+
+  _tableQuery(json: QueryJson): any {
+    const client = knex({ client: this.sqlClient })
+    let query
+    if (!json.table || !json.meta || !json.meta.tables) {
+      throw "Cannot execute without table being specified"
+    }
+    switch (this._operation(json)) {
+      case Operation.CREATE_TABLE:
+        query = buildCreateTable(client, json.table, json.meta.tables)
+        break
+      case Operation.UPDATE_TABLE:
+        if (!json.meta || !json.meta.table) {
+          throw "Must specify old table for update"
+        }
+        query = buildUpdateTable(client, json.table, json.meta.tables, json.meta.table)
+        break
+      case Operation.DELETE_TABLE:
+        query = buildDeleteTable(client, json.table)
+        break
+      default:
+        throw "Table operation is of unknown type"
+    }
+    return query.toSQL()
+  }
+}
+
+export default SqlTableQueryBuilder
+module.exports = SqlTableQueryBuilder

packages/server/src/integrations/base/utils.ts

@@ -0,0 +1,19 @@
+import { QueryJson } from "../../definitions/datasource"
+import { Datasource } from "../../definitions/common"
+
+module DatasourceUtils {
+  const { integrations } = require("../index")
+
+  export async function makeExternalQuery(datasource: Datasource, json: QueryJson) {
+    const Integration = integrations[datasource.source]
+    // query is the opinionated function
+    if (Integration.prototype.query) {
+      const integration = new Integration(datasource.config)
+      return integration.query(json)
+    } else {
+      throw "Datasource does not support query."
+    }
+  }
+
+  module.exports.makeExternalQuery = makeExternalQuery
+}

packages/server/src/integrations/mysql.ts

@@ -262,6 +262,13 @@ module MySQLModule {
       const operation = this._operation(json)
       this.client.connect()
       const input = this._query(json, { disableReturning: true })
+      if (Array.isArray(input)) {
+        const responses = []
+        for (let query of input) {
+          responses.push(await internalQuery(this.client, query, false))
+        }
+        return responses
+      }
       let row
       // need to manage returning, a feature mySQL can't do
       if (operation === operation.DELETE) {

packages/server/src/integrations/postgres.ts

@@ -263,10 +263,18 @@ module PostgresModule {
     async query(json: QueryJson) {
       const operation = this._operation(json).toLowerCase()
       const input = this._query(json)
+      if (Array.isArray(input)) {
+        const responses = []
+        for (let query of input) {
+          responses.push(await internalQuery(this.client, query))
+        }
+        return responses
+      } else {
         const response = await internalQuery(this.client, input)
         return response.rows.length ? response.rows : [{ [operation]: true }]
       }
     }
+  }
 
   module.exports = {
     schema: SCHEMA,